1. Field of the Invention
This invention relates to electrically-operated automotive vehicle systems, and more particularly to an improved electrically-operated automotive vehicle and an electrified roadway over which the vehicle may operate and which supplies electric current to the vehicle.
2. Description of the Prior Art
Electrically-powered automotive vehicles which are operable on smooth road surfaces are well-known and conventionally comprise a storage battery pack which supplies the electrical energy for operating the vehicle on the open road, with the vehicle including charging circuitry to enable recharging of the batteries as by plugging into a conventional electrical outlet. Such vehicles provide pollution-free and economical transportation, but generally are seriously limited in the distance they can travel between battery charges, and operating the vehicle for the maximum time between battery recharging greatly reduces battery life.
Electrically-operated vehicles are also known which are capable of operating both from a battery pack and from an outside source of electrical power such as overhead trolley wires or energized trolley rails, tracks or the like. However, maneuverability of such vehicles has generally been severely limited and the battery-operation has generally been intended only for a limited use as for transferring between trolley lines, turning the vehicle, or other short maneuvers. Accordingly, such vehicles have generally not been found satisfactory for general public use.
Another known electrically-operated vehicle employs a battery pack for supplying the power to the electric motor drive, with an alternate, self-contained power source such as an internal combustion engine being provided to drive a generator for re-charging the batteries and/or providing electrical energy to the drive motors when not operating on the batteries. While this system overcomes the inherent range limit of vehicles powered by batteries alone, the system is relatively expensive to construct, inefficient to operate, and only partially avoids the air pollution problem of conventional internal combustion engine-operated vehicles.
It is also known, for example from U.S. Pat. No. 1,859,343, to provide an electric motor-driven vehicle with electrically conductive tires which contact a series of conductors imbedded in the top surface of a roadway to complete an electric circuit between the imbedded conductors and an overhead line which is engaged by a trolley. The vehicle is able to maneuver over the width of the roadway, within the confines of the imbedded conductors, so long as the trolley maintains electric contact with the overhead line. This patent also discloses the use of an engine-driven generator as an alternate power supply to enable the vehicle to proceed from the specially-designed roadway onto an ordinary road surface.
From the above, it is seen that the prior art electrically-operated automotive vehicles have generally been inherently limited in some respects which have prevented their wide-spread acceptance. It is, therefore, the primary object of the present invention to provide an improved electrified transportation system including a new and improved electrically-operated automotive vehicle and electrified roadway over which the vehicle is operated and which will overcome the limitations of the prior art as discussed above.
Another object of the present invention is to provide an improved electric transportation system which includes an improved electrified roadway over which conventional motor vehicles may be operated with safety and which includes means for providing electric current through the wheels of an improved electrically-operated motor vehicle to operate the vehicle over the roadway.
Another object of the invention is to provide such an improved roadway having spaced parallel electrical contact assemblies with electrically-conducting upper surfaces thereon which are energized successively in predetermined section lengths only upon the application of a predetermined load on the conducting surface.
Another object of the invention is to provide an electrified roadway for providing electric energy to vehicles operating thereon and incorporating improved electric heating means for automatically de-icing the roadway.
Another object of the present invention is to provide an improved electrically-operated motor vehicle which incorporates a battery pack to enable operation of the vehicle on conventional road surfaces and separate extensions of the vehicle electrical circuit which enable the vehicle to pick up current and close an electrical circuit, from at least two normally "dead", separated conductive plates flush imbedded in the roadway surface of each traffic lane, through the vehicle wheels.
Another object is to provide an improved transportation system including an electrically operated vehicle and an electrified roadway including means for supplying electric energy to the vehicle operating thereon, and which vehicle includes battery means for operating the vehicle when off the electrified roadway.
A further object is to provide such a transportation system in which the batteries are automatically maintained at or near full charge when operating the vehicle on the electrified roadway to enable greater freedom of operation of the vehicle and to greatly extend the battery life.